The present invention relates a high amperage solenoid structure and particularly to such a switch structure which operates with current rating in hundreds of amperes for operating of various recreational vehicles, heavy equipment including material handling equipment, electric vehicles, emergency equipment, golf carts and earth moving equipment and the like.
Solenoid switch devices are widely used for interconnecting of power current sources to a load in response to a relatively low level control current. The assignee of this invention has designed commercially successful solenoid switch devices for use in various applications, generally for lower current rating such as automobile starters, lawn tractors and other like applications. Highly successful structures are shown in U.S. Pat. No. 4,521,758 which issued Jun. 4, 1985 and U.S. Pat. No. 5,021,760 which issued Jun. 4, 1991. Both the '758 and '760 patents are assigned to the common assignee of this application. The patents disclose relatively compact solenoid switch units particularly operable in high vibrational environments with improved contact support and enclosure. The prior art structures made under such patents have generally been directed to current loads on the order of 100 amperes, with voltage of 6 and 12 volts. Although the structures as disclosed in the above patents and in other patents may also be suitable for high amperage applications, the present inventors have found certain limitations on prior art systems disclosed and heretofore when applied at higher amperage ratings. Thus, currently some users require a rating of 300 peak amps. High currents require special consideration as to insulation establishing proper contact closure and opening and establishing proper terminal connectors. In addition, short circuiting of the high current output terminals is more critical than conventional low rated capacity applications. However, the mounting and size requirements are generally such as to require a compact device which will operate in various environments encountered in industrial strength solenoid applications, including a very wide range of temperatures, from well below zero to temperatures approaching boiling temperatures.